Blow molding conference highlights all-electric machines
Interest in all-electric blow molding machines is starting to grow in the U.S., long after electric machines became commonplace in Europe. That was one of the themes throughout the 33rd annual Blow Molding Conference, held Oct. 2-4 in Chicago by the Society of Plastics Engineers.
One conference attendee, Bob Jackson, owner of Jackson Machinery Inc., said the benefits of all-electric machines are fueling demand, but one of the challenges to selling the machines is educating buyers and convincing them to try something different.
“This thing is an absolute no-brainer, except for the mentalities of our users,” Jackson said. “The user says: ‘Gee whiz, this thing is something completely different. It will be a real trauma to learn how to use it. I don’t want to do that. We have all-hydraulics. Nobody here knows anything about an electric.’ But you don’t have to know anything about an electric. It’s really exciting.”
Many functions that used to be handled manually now can be handled simply by inputting information into a PLC, Jackson said.
“The PLC sets everything up,” Jackson said. “It remembers mold settings. It can set mechanical settings. It stores recipes for different projects you might be working on that would speed the time to change projects. The hydraulic machines still need someone to push the buttons to change the settings. The electric version sets itself.”
Magic MP SpA introduced its first-generation all-electric machines in 1997 for pharmaceutical applications and began slowly transitioning from hydraulics toward all-electric models.
Magic sells single-stage injection stretch blow molding machines to process PET and extrusion blow molding machines for processing HDPE, high-molecular-weight PE and PP. During the conference, Magic showed a video of its ME-L20/D-1300-T35, a long-stroke blow extrusion molding machine designed to compete against other high-output machines.
The machine’s cavity configuration depends on the product being produced. For example, if the need is for 200-milliliter (ml) yogurt containers, the model would be designed with 24 + 24 cavities; its output would be about 20,000 pieces per hour. If the need is for 500-ml yogurt containers, the cavitation would depend upon the container dimensions; with this model, the clamping units can reach up to 38.5 tons. In this type of application, the machine is equipped with two independent 12-cavity heads to develop a 24-cavity head with a center distance of 50mm. The two heads are fed by two independent extruders that have a 90mm diameter and provide greater precision and reliable distribution and consistency of the parisons.
While the U.S. has been slower to change, there appears to be progress. Magic has just over 125 machines installed in the U.S., and about 30 of those are all-electric. Worldwide, out of about 6,000 Magic blow molding machines, nearly 1,000 are all-electric.
The benefits of all-electric machines include:
• Lower energy consumption,
• Cleaner operation with no need for hydraulic oil,
• Better clamp control,
• More accurate process control,
• 60 percent lower maintenance costs,
• More compact design, and
• Lower machine costs.
“Energy consumption, of course, was one of the major reasons [for the increasing popularity] in the beginning,” said Celestino Spiga, area manager for Magic. “Electric machines use around 40 percent less energy compared to a good hydraulic machine.”
Also, electronic controls and servo motors mean an all-electric machine can be controlled more easily and precisely.
“The capability to repeat the sequence of the process on the electric machine is much better controlled because there is less influence of variations from the outside, which means from the oil,” Spiga said.
On a hydraulic machine, factors including the oil temperature, viscosity and pressure can affect machine performance.
“With the electric unit, you just go from the motor to the mechanical movement,” he said. “The concept is to use the electrical machine or the electrical solution to have better control of the process.”
The consistency of operation leads to a better product, he said.
“We believe that in the U.S., the market for electric machines will grow tremendously in the following years,” Spiga said.
Hesta Blasformtechnik GmbH & Co. is a family-owned business founded in 1948 that manufactures and sells hydraulic, electric and hybrid blow molding machines. The company offers continuous extrusion and accumulator-head blow molding machines.
During the conference, the company discussed its Hesta700 all-electric blow molding machine. The 700 machine features a 700mm linear mold stroke with a clamping force of about 25 tons. The machine is for manufacturing containers up to 5,000ml, according to the company’s website.
At NPE 2018, Hesta will demonstrate an even larger blow molding machine, which features a 900mm linear stroke with a clamping force of nearly 45 tons. The Hesta900 has a 900mm linear stroke and makes containers up to 5,000ml but is not yet available for purchase; the first machine will be exhibited at NPE.
Recent improvements to Hesta’s all-electric models include software that can automatically measure energy consumption during production to help calculate energy costs. In addition, Hesta installed state-of-the-art modems with cell phone cards in them to provide remote service without having to connect the machines to company networks.
Thorsten Bung, Hesta’s director of sales and marketing, said his company is seeing increased interest in all-electric blow molding machines from U.S. plastics manufacturers.
“It is coming along with the rising costs for energy,” Bung said. He estimates Hesta’s all-electric blow molding machines can reduce energy consumption by as much as 60 percent.
During his presentation to attendees, Bung highlighted Hesta’s patented HES system, which adjusts for different mold thicknesses and enables users to set forces from 0 percent to 100 percent. “It compensates for different mold heights,” Bung said. “You install the mold, and if it is 1, 2 or 3 millimeters higher than the other mold, or vice versa, the machine is doing the setup automatically.”
Jackson Machinery became a representative for Hesta in the U.S. and Canada in October 2016. Since then, it has sold about five all-electric Hestas, including an HV200 and a Hesta490.
Jackson said that while the energy savings are significant, he thinks the electric motor has an even more significant advantage. “Everybody talks about the electric [machine] saving energy, but that’s the least of its goodness. The real issue is, it doesn’t break itself,” Jackson said. “It can’t break itself because you have a torque motor that only goes so far. With a hydraulic machine, you walk over, and you turn the pressure up. You get more tonnage, and it breaks things.”
Jackson said an operator of a hydraulic machine that is getting too much flash on a part may turn up the hydraulic pressure — potentially higher than it was designed for. As a result, over time, it will damage tie rods and stress clamps and other parts. An electric machine eliminates that possibility. PLCs and electric motors limit the tonnage that can be delivered.
Price used to be a deterrent to switching from hydraulic to all-electric models, but that is no longer the case. The costs for all-electric machines now are comparable to hydraulic machines or at a 5 percent premium at most, Jackson said.
BBM Maschinenbau und Vertriebs GmbH has been building extrusion blow molding machines since the company’s formation in 1997. The company has put a strong focus on electric machines since 2006, and the continuous improvement of the technology has led to growth in demand, the company said.
One of the company’s newest machines that it was highlighting at the booth was the BBM FD 20E, what the company calls the most compact machine in the world for 20-liter stackable storage containers. Introduced in 2016, it has a footprint of about 108 square feet and 20 tons of clamping force.
The machine features twin-extruder technology with new high-output extruders for high-modulus PE (HMPE), a resin with high-impact strength.
The FD 20E includes automatic electric clamping force adjustment and a touch-screen controller with remote control. The company estimates energy savings of 40 percent to 50 percent compared to hydraulic machines, as well as lower maintenance costs due to a lack of oil, valves and tubes.
The company also recently introduced a single-station injection blow molding machine called EcoPET for production of PET bottles in cosmetic, detergent, pharma and food packaging.
“We introduced our first fully electric blow molding machines in 2006 in Europe, and we have seen that over recent years the awareness of saving energy and to going to more state-of-the-art manufacturing has also come to the States,” said Sebastian Walter, BBM director of business development. “We are now the second-largest manufacturer of extrusion blow molding machines in Europe, and 90 percent of the machines we build are electric. There are just a lot of advantages from power saving, from easier maintenance, from repeatability on the machine movements, and reduced start-up times as compared to a hydraulic system.”
Maintenance is easier and less costly because all-electric machines contain fewer components. Processors are starting to realize the added value, he said. “People have a certain comfort zone, and they know hydraulic machines,” Walter said. “If there is something new, it’s normal that there is a psychological barrier.”
Bruce Geiselman, senior staff reporter
For more information
BBM Maschinenbau und Vertriebs GmbH,
Langenberg, Germany, 49-5248-82-38-0, www.bbm-germany.com
Hesta Blasformtechnik GmbH & Co.,
Göppingen, Germany, 49-7161-504-67-0, http://hesta.de/en/
Jackson Machinery Inc.,
Port Washington, Wis., 262-284-1066, www.jacksonmachinery.com
Magic MP SpA,
Monza, Italy, 39-0392-301096, www.magicmp.it/en